When you come across a movie you’ve never heard of starring a bunch of people you have heard of, it’s usually artsy fartsy (think “Gosford Park” or “Magnolia”). But sometimes, it’s just fartsy. The methane delivery system known as “Airheads” (1994) features Brendan Fraser, Steve Buscemi and Adam Sandler, along with Michael McKean, Joe Mantegna, David Arquette, Ernie Hudson, Chris Farley, Judd Nelson and Michael Richards. Loser L.A. rockers with toy guns and underdeveloped career plans hijack a radio station. Hijinks ensue. Thin plot. Physical comedy. Ninety-two minutes of your life you’ll never get back. Are you ready to rock?